Polymers of acrylic esters of salicyloylbenzoylmethane



3,375,24 Patented or. 23, 1965 This invention relates to organic polymeric structures and, particularly, to shaped articles such as polymeric films suitable for outdoor use.

Many organic polymeric structures, such as structures of polyethylene, polypropylene, poly(vinylidene chloride) and the like deteriorate rapidly when subjected to sunlight. The materials are sensitive to light in the ultraviolet range, particularly in the wave length range of 2900-3800 A. Exposure to the ultraviolet light tends to embrittle the structures and reduce the level of their electrical and physical properties substantially. Some polymers acquire an undesirable color upon exposure to ultraviolet light.

The use of certain chemical compounds as ultraviolet light absorbers in mechanical mixture with the polymers is known. Thus, compounds such as benzophenones or salicyclic acid esters have been incorporated in the molten polymer prior to forming a structure or they have been coated on the surface of the polymeric structure. In either case, the protection aflorded by these compounds is not permanent. The compounds gradually exude to the film surface and disappear from the polymeric structure due to mechanical abrasion or volatility.

The object of the present invention is to provide a sub stantially permanent weather-resistant organic polymeric shaped article, particularly a self-supporting film, suitable for outdoor use. It is a further object to provide a process for incorporating ultraviolet light absorbent compounds into the polymeric articles so that the compounds are firmly attached to the articles. Other objects will appear hereinafter.

The objects are accomplished by a copolymer of 90-9999 mole percent of at least one unsaturated compound, compound A, having the structural formula:

wherein R, is selected from the group consisting of hydrogen, halogen and alkyl having 1-4 carbon atoms, preferably wherein R is hydrogen or an alkyl group having 1-4 carbon atoms,

R is selected from the group consisting of hydrogen,

halogen, alkyl of l-4 carbon atoms, carboalkoxy, carboaryloxy, phenyl, acetoxy, acetyl and cyano, preferably wherein R is hydrogen and .01- mole percent, preferably .1-10 mole percent, of at least one unsaturated compound, compound B, having the stuctural formula:

wherein R is selected from the group consisting of hydrogen and alkyl having l-3 carbon atoms,

R, is selected from the group consisting of alkyl having 1-18 carbon atoms and wherein R is selected from the group consisting of hydrogen,

halogen, alkyl and alkoxy,

the copolymer preferably having an inherent viscosity of at least 0.3.

Specifically, the objects are accomplished by a copolymer of at least one polymerizable compound selected from the group consisting of ethylene, propylene, styrene, vinylidene chloride, vinyl acetate, vinyl chloride, vinyl fluoride, acrylonitrile and butyl acrylate and .01-10 mole percent, preferably .l-lO mole percent, of at least one ethylenically unsaturated compound selected from the group consisting of (o-methacryloxybenzoyl) benzoylmethane, (o-methacryloxybenzoyl)acetylmethane, (oacryloxybenzoyl)benzoyl.methane, (o-acryloxybenzoyl)- stearylmethane, (o-methacryloxybenzoyl)toluoylmethane, and (o-methacryloxybenzoyl)chlorobcnzoylmethane, the copolymer having an inherent viscosity of at least 0.3.

It is also possible to use a homopolymer of compound B in the form of a coating on a shaped article of or as part of a blend with a polymer of compound A, polyesters and epoxy resins. Thus, shaped articles of polymers (homopolymers and copolymers) of ethylene, propylene, butene-l, pentene-l, hexene-l, vinyl chloride, vinylidene chloride, methyl, ethyl, butyl, octyl, ethylhexyl, cyclohexyl and phenyl acrylates and methacrylates, vinyl acetate, vinyl propionate, acrylonitrile, polyethylene terephthalate, etc., can be coated with homopolymers of compound B.

The homopolymer coating may be applied to the shaped articles from a solution of the homopolymer in a solvent such as ethyl acetate, dioxane, acetone, toluene, benzene, etc., or a dispersion of the homopolymer in water or in a solvent. Coating may be accomplished by a dipping process, a brushing process or a spraying process. It is also possible in some cases to melt press the homopolymer on the polymeric shaped article. In order to achieve effective protection from ultraviolet light, the ultimate homopolymeric coating should have a thickness of at least 0.1 mil. Although the coating can be thicker, it is undesirable from an economic standpoint to use coating thicknesses greater than about 2 mils. For most substrates, the homopolymeric coating need not be any thicker than 0.5 mil.

When used in a blend, it is desirable to incorporate 05-20% by weight of the homopolymer of compound B into the thermoplastic polymeric resin prior to using the resin either as a coating or a shaped article such as a selfsupporting film, a filament, a tube, a rod, and the like or as an adhesive. The incorporation process may be accomplished by any of the conventional procedures known to those in the art such as milling or wet blending (dissolving the polymers in a common solvent).

Although incorporation of the homopolymers of this invention with thermoplastic polymeric resins provides some improvement for all the polymers enumerated previously, the blending procedure is particularly effective with polymers having polar bonds. Such polymers include the aerylate and methacrylate polymers, vinyl acetate polymers, vinyl chloride polymers, vinylidene chloride polymers, polyesters and epoxy resins.

Of particular interest is the blending of the homopolymers of compound B with adhesive polymeric resins such as the acrylic, epoxy and polyester adhesive resins. The adhesive resins containing the homopolymers of the invention may then be used as a coating or in a laminate. When used in a laminate. the adhesive containing the liomopolymer of the invention will tend to protect the substrate but more important the adhesive itself will be resistant to ultraviolet light and, thus, provide a weatherable bond that maintains the laminate for extended periods. Among the polyesterbased adhesives which are benefited by the incorporation of the homopolymers of compound B are those polyester and copolyester compositions disclosed in U.S. Patents Nos. 2,765,251, 2,623,- 033, 2,698,239 and 2,698,241 which are usually obtained by reacting a slight stoichiometric excess of ethylene glycol with dimethyl esters of terephthalic, sebacic, isothalic, and/or adipic acids. Among the acrylic adhesives which may be used with the homopolymers of compound B are those disclosed in U.S. Patents Nos. 2,464,826 and 2,949,- 445. The epoxy adhesives which are benefitted by incorporating the homopolymers of compound B include those that are prepared by reaction of epichlorohydrin and bisphenol A and sold under the names Epon" [004, 1007, 1009, and Bonding Agent R- 313 It should also be understood that the homopolymers of compound B may be used alone as the basis for shaped articles that are resistant to degradation by ultraviolet light. These homopolymers may be extruded at elevated temperatures in the form of self-supporting films, filamentsQrods, tubes, etc. Alternatively. the homopolymers may be cast from solutions in certain solvents such as ethyl acetate methyl ethyl ketone, benzene, toluene, etc., in the form of a shaped article.

In all cases, the homopolymers and the copolymers may be used along with pigments, fillers, heat stabilizers, plasticizers, or other ultraviolet light absorbers if desired as long as these additives do not detract from the effectiveness of the polymers.

POLYMERIZATION OF STABILIZING MONOMERS The process for preparing the polymers (copolymers with to methacryloxybenzoyl)benzoylmethane, (o-acryloxy benzoyl benzoylmethane, (o-methacryloxybenzoyl)acetylmethane, (o-methacryloxybenzoyl)toluoylmethane, (o-

acryloxybenzoyl)stearylmcthane and benzoyl chlorobenzoylmethane.

The next step involves subjecting the monomer(s) preferably in a solvent such as hexane, benzene, toluene, toa temperature of 40 to 300 C. and a pressure of l-3000 atmospheres in the presence of a catalyst for a contact time sufiicient to form the polymer, usually at least 20 seconds for a continuous process and at least 3 minutes for a batch process, and then isolating the resulting copolymer or homopolymer.

In the preparation of copolymers, when high pressures are used, 800 atmospheres and above, a conventional peroxide (di-tertiary butyl peroxide) or azo catalyst (alpha, alpha'-azobisdicyclohexanecarbonitrile) may be used and the temperature is preferably 25l75 C.

It is believed that the essential feature of this type of catalyst, or more properly termed initiator is that it is capable of generating free radicals. These free radical initiators, whether they be generated from a peroxide (o-methacryloxy- 1 Manufactured by Shell Chemical Company. a Manufactured by C. H. Briggs Company.

compound or from an azo-type compound combine with a polymerizable monomer to form a new free radical; the new free radical combines with another monomer molecule to form still another free radical; this process is repeated until there is propagated a long polymer chain, as is well known in the art. Polymer chain growth terminates when the free radical-bearing polymer fragment encounters another free radical, which, for example, may be another growing polymer chain or an initiator free radical.

Typical peroxides which function as initiators includes benzoyl peroxide, tertiary-butyl peracetate, di-tertiarybutyl peroxide, di-tertiary-butyl peroxydicarbonate, 2,2- bis(tertiarybutylperoxy) butane, dimethyl dioxide, diethyl dioxide, dipropyl dioxide, propyl ether dioxide and propyl methyl dioxide. Organic hydroperoxides also applicable are, for example, tertiary-butylhydroperoxide, cumene hydroperoxide, ethyl hydroperoxide, and can be used to initiate polymerizations of this. Combinations such as ammonium persulfate with a reducing agent can also be used. Typical azo compounds which decompose to libcrate free radicals for initiation of polymerization include such catalysts as alpha, alpha'-azobisdicyclohexanecarbonitrile, alpha, alpha'-azobisisobutyronitrile, triphenylmcthylazobenzene, l l '-azodicycloheptanecarbonitrile, alpha, alpha'-azobisisobutylramide, lithium azodisulfonates, magnesium azodisulfonate, dimethyl alpha, alphaazodiisobutyrate, alpha, alpha-azobis(alpha, gammadimethylvaleronitrile) and alpha, alpha'-azobis(alpha, beta-dimethylbutyronitrile) For homopolymerization of compound B, it has been found that only the aforementioned azo catalyst are sulficiently effective to provide adequate yields.

Coordination catalysts, as defined in U.S. Patent 2,822,357, may also be used to effect copolymerization. Specifically, such coordination catalysts are composed of:

(A) A compound containing at least one metal of the group consisting of metals of Groups IVa, Va and Vla of the Periodic Table, iron, cobalt, copper, nickel and manganese, said metal having directly attached thereto at least one substituent from the group consisting of halogen, oxygen, hydrocarbon and -O-hydrocarbon;

and

(B) A reducing compound selected from the group consisting of metal hydrides and compounds having a metal of Groups I, II and III of the Periodic Table, said metal being above hydrogen in the electromotive series, attached directly through a single bond to a carbon atom, said carbon atom selected from the group consisting or trigonal carbon and tetrahedral carbon.

In the above definitions, Periodic Table means Mendeleelfs Periodic Table of the Elements 25th ed., Handbook of Chemistry and Physics, published by the Chemical Rubber Publishing Co. Specific examples of compound (A) included in the above definition are titanium tetrachloride, titanium tetrafluoride, zirconium tetrachloride, niobium pentachloride, vanadium tetrachloride, vanadyl trichloride, tantalum pentabrornide, cerium trichloride, molybdenum pentachloride, tungsten hexachloride, cobaltic chloride, ferric bromide, tetra(2-ethylhexyl)-titanate, tetrapropyl titanate, titanium oleate, octylene glycol titanate, triethanolamine titanate, tetraethyl zirconate, tetra(chloroethy1) zirconate, and the like. Specific examples of compound (B) in this definition are phenyl magnesium bromide, lithium aluminum tetraalkyl, aluminzm trialkyl, dimethyl cadmium, diphenyl tin, and the li e.

Copolymerization, as well as homopolymerization, is preferably carried out in a solvent medium. Among the solvents which have been found useful in the present invention are hydrocarbons and halogenated hydrocarbons: hexane, benzene, toluene, cyclohexane, bromobenzcne,

chlorobenzene, o-dichlorobenzene, tetrachloroethylene, dichloromethane and l,l,2,2-tetrachloroethane. Heterocyclic compounds such as tetrahydrofuran, thiophene and dioxane may also be used. The preferred solvents, particularly for homopolymerization, are the nonpolar and aromatic solvents such as n-hexane, benzene, cyclohexane, n-octane, n-decane, dioxane, carbon tetrachloride and para-xylene. It has also been found desirable for homopolymerization of compound B to use concentrations of the monomer, compound B, in the solvent in the range of 2 to 20% by weight. In some instances, copolymerization may be effected without a solvent or in an emulsion or slurry system.

In copolymerization, the ratio of the light stabilizing monomer, compound B, to ethylene and/or other monomer, compound A, reacted therewith should be such that the final copolymer is composed of .01-10 mole percent of the stabilizing compound and 99.99-90 mole percent of the other monomer or monomers. Less than .01 percent of the stabilizer does not provide adequate protection against ultraviolet light. More than 10 percent tends to affect adversely the physical properties of the basically polyethylene or polypropylene, etc., structure. Between 0.1 and 10 percent provides the best protection against ultraviolet light. It has been found that the reaction is very efficient so that a reaction mixture of about 01-10 mole percent of the stabilizing monomer and about 99.99- 90 mole percent of the remaining monomer or monomers usually will provide the desired polymer product.

The polymer product, in its preferred form (i.e., reaction product of a light stabilizing monomer and ethylene or the like or the homopolymer) is a substantially linear polymer having pendant groups of the formula:

wherein R is selected from the group consisting of alkyl having 1-18 carbon atoms and wherein R is selected from the group consisting of hydrogen,

halogen, alkyl and alkoxy,

the polymer having an inherent viscosity of at least 0.3.

The determination of the structure is accomplished by Infrared Spectral Techniques 3 known to those skilled in the art. The majority of the infrared spectra herein were taken on pressed films by the use of a Perkin-Elmer Model 21 Spectrophotometer and a Perkin-Elmer Infracord Spectrophotometer.

Measurements of ultraviolet light absorption were carried out in accordance with procedures described in Analytical Chemistry by C. R. N. Strouts, I. H. Gilfillan and H. N. Wilson, Volume II, Chapter 22, Oxford University Press, 1955.

The invention will be more clearly understood by referring to the examples which follow, Example 1 representing the best mode contemplated for practicing the invention. It is understood that the examples, although .5 illustrating specific embodiments of the present inven tion, should not be considered limitative of the invention.

The light stability test used in the examples was carried out by exposing the films to the action of a bank of Westinghouse Sunlamps for the periods indicated.

Inherent viscosity, which is directly related to the molecular weight of the polymer, is defined by L. H. Cragg in the Journal of Colloid Science, Volume I, pages 261-9 (May 1946) as:

Inherent viscosity:

ln relative viscosity C where relative viscosity is the ratio of the solution viscosity to the solvent viscosity, and C is the concentration of solute in solution measured as grams of polymer per ml. of solution.

The ferric chloride test for the presence of phenolic groups is described by Wesp and Brode in the Journal of American Chemical Society, 56, 1037 (1934).

Example 1.-Preparation of (o-methacryloxybenzoynbenzoylmethan'e and its copolymerization with ethylene A mixture of 5.0 grams (0.021 mole) of salicyloylbenzoylmethane and 2.8 grams (0.027 mole) of methacrylyl chloride was treated with 10 m1. of anhydrous pyridine with stirring. After standing for one hour at room temperature, the reaction mixture was poured with vigorous stirring into 150 ml. of 3% aqueous hydrochloric acid containing approximately 50 grams of ice. The mixture was then extracted with ether. The ether extract was then dried over anhydrous sodium sulfate and the ether was evaporated in a vacuum oven to leave a light-yellow oil. Infrared analysis of the oil showed the presence of ester absorption at 1725 cm.- and bonded carbonyl at 1,650 cmf On testing with ferric chloride solution, the material showed phenolic groups to be absent.

The chemical analysis was: carbon, 74.07%; hydrogen, 4.96% (calculated for C H O carbon, 74.01%; hydrogen 5.23%). The product was (o-methacryloxybenzoyl)benzoylmethane.

In a 300 ml. shaker tube was placed a solution of 112 ml. of benzene, 0.2 gram of a,a'-azodicyclohexanecarbonitrile and 0.5 gram of (o-methacryloxybenzoyl)benzoylmethane. Sufiicient ethylene was pressured into the tube at room temperature to give an autogenous pressure of 13,000 p.s.i. at the polymerization temperature of 115 C. The polymerization was carried out for 1.5 hours, and the product was purified by washing with methanol in an Osterizer. A yield of 20.2 grams of copolymer was obtained. Reprecipitation of the copolymer from toluene showed no composition change on examination with infrared absorption, indicating that a true copolymer had been formed. Its inherent viscosity, taken on a solution of 0.1 gram of the polymer in 100 ml. of alpha-chloronaphthalene at C. was 0.81.

A 3-4 mil thick film was formed by pressing a onesquare inch sample of the dried copolymer under 30 tons pressure at 100 C. The amount of light stabilizer present in the copolymer was determined to be about 0.2 mole percent.

The film of the copolymer was flexible after 600 hours exposure to a bank of Westinghouse F-S ultraviolet sunlamps. A polyethylene control film, after hours exposure, cracked upon flexing.

Examples 2-7 Following substantially the procedure of Example 1, copolymers of the following monomers were prepared using the catalysts shown in the following table, Table 1 (Examples 4-6 involved atmospheric pressure polymerizations under nitrogen):

TABLE I Inherent Viscosity Mole Percent Compound B Com- Exnmplo pound A Catalyst Propylone.

0.5 (o-acryloxy- 0. 41

benzoy )benzoyl-mothane.

0.4 (omethacryloxybenzoylJ- benzoylmethane.

0.3 (o-acryloxybenzoyl)steurylmethane.

0.5 (o-methncryloxybenzoyD- benzoylmethane.

0.3 (o-acryloxybenzoyl)benzoylmothane.

Al ha,nlpha'-azolcyclohexnnecarbonitrlle. Alpha,alpha-azoblslsobutyronitrile. 1

Butyl Acrylate.

Vinyl -.do 0. 01

Acetato.

Styrene...

Benzoyl peroxldm. 0. 71

Aerylo Ammonium pernitrlle.

sulfate/sodium blsulflteln aqueous medium. Al ha,al ha'-azolcyelo exanecarbonltrile.

0.2 (o-methncryloxybenzoyl)- acotylmethanc.

Vinyl Fluoride.

1 ltlensured in dlmethylsultoxlde. 1 Measured in hexnmethylphosphoramlde.

The number of hours of successful exposure to ultraviolet light without cracking upon flexing for copolymer films of Examples 2-6 prepared as in Example 1 compared to the duration of exposure that caused a control film of the homopolymer of compound A to'crack upon flexing is provided in the following table, Table II:

TAB LE II Duration of exposure to copolymer of -compound *A/compound B Duration of exposure to control homopolymer of compound A Example A mixture consisting of 25 ml. of vinylidene chloride, 50 ml. of benzene, 0.1 gram of a azobisisobutyronitrile and 1.0 gram (o-methacryloxybenzoyl)benzoylmethane dissolved in 50 ml. of benzene was refluxed under a nitrogen atmosphere. A vigorous reaction occurred and a white product was deposited in the flask. The product was coagulated; washed by the addition of methanol; and dried.

Infrared analysis revealed strong absorption at 1725 and 1650 cmr characteristic of ester and bonded carbonyl absorption, respectively. A maximum ultraviolet absorption at 3500 A., characteristic of the aromatic betadiketones in carbon tetrachloride, was also apparent. The copolymer, containing about 2 mole percent of the methacrylic ester units, had an inherent viscosity of 0.70.

A film was made by pressing a one-square inch sample under 30 tons pressure at 150 C. This film remained flexible after 300 hours exposure to ultraviolet light, whereas a vinylidene chloride control film after 30 hours exposure, cracked upon flexing.

Examples 9-12.--Preparation of laminar structures (o-methacryloxybenzoyl)benzoylmethane described in Example 1 was laminated to a S-mil thick polyethylene film. The latter had been melt pressed from low density polyethylene prepared according to the method described in US. Patent No. 2,153,553. A laminate was prepared by placing a 4" diameter sample of each film together and melt pressing the combination at a temperature of 100- 110 C. using a pressure of tons.

Under exposure to a bank of ultraviolet sunlamps, with the stabilizer-containing copolymeric film adjacent to the lamps, this laminate remained flexible after 1500 hours of exposure. A control sample of 6-mil thick polyethylene film became embrittled after a period of 275 hours exposure.

For Examples 10 and 11, a film of high density polyethylene made by melt pressing polyethylene prepared as described in US. Patent No. 2,816,883 and a film of polypropylene were each laminated to ethylene/(o-methacryloxybenzoyl)benzoylmethane copolymer films. In Example 12, the ethylene/ (o-methacryloxybenzoyl)benzoylmethane copolymer film was laminated to a polyethylene terephthalate film by melt pressing at a temperature of about 150 C. All laminates showed enhanced resistance to ultraviolet light degradation over the high density polyethylene, the polypropylene and the polyethylene tereph thalate films alone.

Examples 13 and 14 The monomer prepared in Example 1 was homopolymerized by introducing 2 grams of (o-methacryloxybenzoyl) benzoylmethane, 10 ml. of toluene and 0.2 gram of a,a'- azobisisobutyronitrile into a flask previously flushed with nitrogen. This mixture was heated for 2 hours at a temperature of C., during which period an atmosphere of nitrogen was maintained. Aportion of the reaction mixture was cooled to room temperature and used directly for coating the substrate as described below. The remainder of the reaction mixture was placed in a vacuum oven at 50 C. where the solvent was evaporated. The inherent viscosity of the solid product remaining was measured on a solution of 0.1 gram of the polymer in ml. of alpha-chloronaphthalene at C. and found to be 0.38.

A 4-mil thick sheet of polyethylene film was prepared in the conventional manner from Alathon 10 polyethylene resin and treated to improve its adhereability by the process described in US. Patent 2,715,076. The film was coated with the above prepared solution of the homopolymer. The solvent was evaporated by heating coated film in an oven at 50 C. leaving a coating 0.3 mil thick of the ultraviolet light stabilizing homopolymer.

When exposed to the action of a bank of Westinghouse F-S 20-T-12 sunlamps, the coated film showed no evidence of cracking after 2,000 hours of such exposure. A control uncoated polyethylene film cracked when flexed after only 250 hours exposure.

In Example 14, 1 percent by weight of the above homopolymer was blended with the Alathon 10 polyethylene resin prior to forming a 4-mil thick film. The resulting film withstood 800 hours of exposure to the bank of Westinghouse sunlamps.

Example 15 Poly(o-acryloxybenzoyl)benzoylmethane was prepared substantially in the manner described for Example 13. The homopolymer in a solution of toluene was coated on a polypropylene film to form, after evaporation of the solvent, an 0.3-mil thick coating.

The coated film withstood 1500 hours of exposure to the bank of Westinghouse sunlamps, whereas poly(propylene) control films failed after only 25-50 hours of exposure.

Example I6.Modification of acrylic adhesive To a solution of Eastman 910 methyl cyanoacrylate adhesive there was added 1% by weight of the adhesive solids of the polymer of (o-acryloxybenzoyhbenzoylmethane prepared substantially as described in Example 13. This adhesive solution was then used to fasten a strip of rubber to a chromium plated steel substrate. After 18 months outdoor exposure the rubber strip remained firmly adhered to the substrate; a similar adhesive bond made on a rubber strip attached with the same adhesive but without the added ultraviolet light stabilizer was no longer intact at the end of the time.

Example 17.-Mdificati0n of polyester adhesive To a solution of 17 parts by weight of a 60/40 weight ratio ethylene terephthalate/ethylene sebacate copolyester (prepared as described in U.S. Patents Nos. 2,623,- 031 and 2,623,033) in 83 par-ts by weight of carbon tetrachloride then was added 1% by weight of the copolyester solids of poly(o-methacryloxybenzoyl)benzoylmethane. A thin layer of this adhesive composition was brushed on one surface of each of two 3-mil thick sheets of polymeric linear .terephthalate film. The solvent was evaporated and the adhesive coated sheets were pressed together with a pressure of 500 pounds per square inch at 90 C. for 5 minutes. The adhered laminate was then exposed to a bank of ultraviolet sunlamps for 1000 hours. At the end of this time the sheets were still firmly adhered whereas a control laminate adhered with the same adhesive which did not have the added polymeric light stabilizer showed almost no adhesion under the same treatment.

Example 18.M0difica1ion of epoxy adhesive To a solution of Epon 1007 adhesive obtained from Shell Chemical Company there was added 1% by weight of adhesive solids of the polymer of (o-methacryloxybenzoyl)acetylmethane. A thin layer of this adhesive composition was brushed on one surface of each of two sheets of tetrafluoroethylene/hexafluoropropylene copolymer film which had previously been treated in an electrical discharge in an atmosphere of nitrogen and the vapor of glycidyl methacrylate. The surfaces bearing the adhesive were pressed together for 20 minutes at 70 C. at a pressure of 75 pounds per square inch. The laminate was then exposed to a bank of ultraviolet sunlamps for 1000 hours. At the end of this time the laminate showed no impairment in bonding strength of the adhesive. A control laminate made with the same adhesive which did not contain the light stabilizer showed a reduction in bond strength of about 30% after the same period.

As indicated in the examples and in the foregoing discussion, the light-stabilizing monomers can be homopolymerized or copolymerized with polymerizable unsaturated compounds such as ethylene, propylene, vinylidene chloride, vinyl chloride, vinyl fluoride, butyl acrylate, acrylonitrile, styrene, vinyl acetate, etc. For copolymerization, any ethylenically unsaturated compound falling within the formula Ra may be used. Thus, butene-l, pentene-l, hexene-l, butyl methacrylate, cyclohexyl methacrylate, etc., may also be used.

As polymeric structures, self-supporting films, supported films (laminates and coatings), filaments, tubing, etc., can be formed from these polymers for important commercial applications. Thus, these structures will find utility in the preparation of greenhouses, exterior screening, garden hose, as part of automobile exteriors, etc.

It is also possible to graft copolymerize the polymerizable light-stabilizing monomer onto a prepolymerized ethylenic or other unsaturated compound of the type defined hereinbefore. This would be especially useful where it was desired to confine the light-stabilizing composition to the surface as a coating.

The main advantage of the copolymers of this invention is that a high proportion of the light-stabilizing component can be incorporated in a copolymer to give enhanced resistance to degradation from ultraviolet light without causing haziness in the film. It is also clear that the light-stabilizing function is essentially permanent. A further advantage is that a separate processing step, such as milling or dissolution, is not required to incorporate the light-stabilizing composition into the base polymer. The copolymer and its light-stabilizing qualities are provided during the one-step copolymerization. Moreover, incorporation of the light stabilizer by copolymerization in this manner can be done in conventional polymerization equipment.

The homopolymers of this invention are also quite versatile. They provide enhanced light stabilization, particularly when used in blends with other polymeric materials. As a coating, they offer the advantage that the light absorber may be concentrated where it is most needed, on the surface of the degradable shaped article.

Having fully described the invention, what is claimed is:

1. A weather-resistant polymeric composition consisting essentially of a copolymer of -9999 mole percent of at least one unsaturated compound having the structural formula:

wherein R is selected from the group consisting of hydrogen,

halogen and alkyl having 1-4 carbon atoms,

R; is selected from the group consisting of hydrogen, halogen, alkyl of 1-4 carbon atoms, carboalkoxy, phenyl, acetoxy, carboaryloxy, acetyl and cyano' and .01-10 mole percent of at least one unsaturated compound having the structural formula:

wherein R is selected from the group consisting of hydrogen and alkyl having 1-3 carbon atoms, and R is selected from the group consisting of alkyl having l-18 carbon atoms and and .Oil0 mole percent of at least one unsaturated compound having the structural formula:

O O iii-CHg-i-Ra wherein R is selected from the group consisting of hydrogen and alkyl having 1-3 carbon atoms, and R is selected from the group consisting of alkyl having 1-l8 carbon atoms and wherein R \is selected from the group consisting of hydrogen,

halogen, alkyl and alkoxy.

3. A weather-resistant self-supporting film which consists essentially of a copolymer of 90-9999 mole percent of at least one unsaturated compound having the structural formula:

Ri Hzc=l l 1'1, wherein R is selected from the group consisting of hydrogen and alkyl having I-3 carbon atoms, and

R is selected from .the group consisting of alkyl having l l8 carbon atoms and wherein R is selected from the group consisting of hydrogen,

halogen, alkyl and alkoxy. 4. A homopolymer of an unsaturated compound having the structural formula:

O 0 li-CHg-lL-Rq wherein R is selected from the group consisting of hydrogen and alkyl having 1-3 carbon atoms, and

12 R is selected from the group consisting of alkyl having l-l8 carbon atoms and R6 wherein R is selected from the group consisting of hydrogen,

halogen, alkyl and alkoxy.

5. A weather-resistant shaped article which consists essentially of a blend of a polymer selected from the group consisting of polyesters and epoxy resins and unsaturated compounds having the structural formula:

R is selected from the group consisting of hydrogen,

halogen and alkyl having 1-4 carbon atoms,

R, is selected from the group consisting of hydrogen, halogen, alkyl of l-4 carbon atoms, carboalkoxy, phenyl, acetoxy, carboaryloxy, acetal and cyano with 05-20% by weight of the homopolymer of claim 4.

7. A weather-resistant shaped article which consists essentially of a shaped article coated with a coating of the homopolymer of claim 4, said coating having a thickness of at least 0.1 mil.

8. A weather-resistant self-supporting film which consists essentially of a base film coated with a coating of the homopolymer of claim 4, said coating having a thickness of at least 0.1 mil.

9. A laminate consisting essentially of a base adhereably associated with a copolymer of at least one unsaturated compound having the structural formula:

RI HgC=( 1'1. wherein R is selected from the group consisting of hydrogen,

halogen and alkyl having 1-4 carbon atoms,

R, is selected from the group consisting of hydrogen, halogen and alkyl of 1-4 carbon atoms, carboalkoxy, phenyl, acetoxy, carboaryloxy, acetyl and cyano,

and 0.1-10 mole percent of at least one unsaturated compound having the structural formula:

wherein R, is selected from the group consisting of alkyl having l-i8 carbon atoms, and

wherein R, is selected from the group consisting of hydrogen,

halogen, alkyl and alkoxy.

10. A substantially linear polymer consisting essentially of the following recurring units:

i. ii i.

and

lanai...

wherein R, is selected from the group consisting of hydrogen,

halogen and alkyl having 1-4 carbon atoms,

R; is selected from the group consisting of hydrogen, halogen, alkyl of l-4 carbon atoms, carboalkoxy, phenyl, acetoxy, carboaryloxy, acetyl and cyano,

R is selected from the group consisting of hydrogen and alkyl having 1-3 carbon atoms, and

R is selected from the group consisting of alkyl having l-18 carbon atoms and i4 wherein R, is selected from the group consisting of hydrogen,

halogen, alkyl and alkoxy.

11. A composition as in claim. 1 wherein at least one unsaturated compound is ethylene.

12. A composition as in claim 1 wherein at least one unsaturated compound is propylene.

13. A composition as in claim 1 wherein at least one unsaturated compound is styrene.

14. A composition as in claim 1 wherein at least one unsaturated compound is vinylidene chloride.

15. A composition as in claim 1 wherein at least one unsaturated compound is vinyl acetate.

16. A composition as in claim 1 wherein at least one unsaturated compound is vinyl chloride.

17. A composition as in claim l'wherein at least one unsaturated compound is vinyl fluoride.

18. A composition as in claim 1 wherein at least one unsaturated compound is acrylonitrile.

19. A composition as in claim 1 wherein at least one unsaturated compound is butyl acrylate.

20. A composition as in claim 1 wherein at least one unsaturated compound is (o-methacryloxybenzoyl)benzoylmethane.

21. A composition as in claim 1 wherein at least one unsaturated compound is (o-methacryloxybenzoyl)acetylmethane.

22. A composition as in claim 1 wherein at least one unsaturated compound is (o-methacryloxybenzoyDtoluoylmethane.

23. A composition as in claim 1 wherein at least one unsaturated compound is (o-methacryloxybenzoyl)chlorobenzoylmethane.

24. A composition as in claim 1 wherein at least one unsaturated compound is (o-acryloxybenzoyDbenzoylmethane.

25. A composition as in claim 1 wherein at least one unsaturated compound is (o-acryloxybenzoyl)stearylmethane.

References Cited in the file of this patent UNITED STATES PATENTS 2,938,883 Raich May 31, 1960 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,175,024 March 23, 1965 Stanley Tocker It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below. 1

In the heading to the printed specification, line 7, for "Ser. No 58,824" "read Ser. No. 54,824 column 4,

line 19, aft-er "this" insert kind line 32, for "catalyst" read catalysts column 10, line 61, for "consist" read consists Signed and sealed this 7th day of September 1965.

(SEAL) v A (test: r

' i ERNEST w. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents r 

10. A SUBSTANTIALLY LINER POLYMER CONSISTING ESSENTAILLY OF THE FOLLOWING RECURRING UNITS: 